docs: def from_mpl(fig, savefig_kw=None):
      """Create a SVG figure from a ``matplotlib`` figure.
  
      Parameters
      ----------
      fig : matplotlib.Figure instance
  
      savefig_kw : dict
           keyword arguments to be passed to matplotlib's
           `savefig`
  
  
  
      Returns
      -------
      SVGFigure
          newly created :py:class:`SVGFigure` initialised with the string
          content.
  
  
      Examples
      --------
  
      If you want to overlay the figure on another SVG, you may want to pass
      the `transparent` option:
  
      >>> from svgutils import transform
      >>> import matplotlib.pyplot as plt
      >>> fig = plt.figure()
      >>> line, = plt.plot([1,2])
      >>> svgfig = transform.from_mpl(fig,
      ...              savefig_kw=dict(transparent=True))
      >>> svgfig.getroot()
      <svgutils.transform.GroupElement object at ...>
  
  
      """
  
      fid = StringIO()
      if savefig_kw is None:
          savefig_kw = {}
  
      try:
          fig.savefig(fid, format='svg', **savefig_kw)
      except ValueError:
          raise(ValueError, "No matplotlib SVG backend")
      fid.seek(0)
      fig = fromstring(fid.read())
  
      # workaround mpl units bug
      w, h = fig.get_size()
      fig.set_size((w.replace('pt', ''), h.replace('pt', '')))
  
      return fig